Interpretive Summary: Type 2 diabetes affects more than 20 million people in the US with millions more worldwide and the incidence is expected to double in the next two decades. The causes of diabetes are not entirely clear but diet certainly plays an important role. We have shown previously that products in cinnamon improve insulin activity in vitro. In this study we determined the effects of cinnamon on the blood sugar and fats of people with type 2 diabetes. Glucose, triglycerides, total cholesterol and LDL cholesterol (the bad form of cholesterol) were all improved by eating 1, 3 or 6 grams of cinnamon per day for 40 days. Improvements were better after 40 than 20 days and all three levels of cinnamon showed similar effects. This study demonstrates that cinnamon improves the blood sugar and fats of people with type 2 diabetes and is likely to also be of benefit to people with elevated levels of blood sugar and fats.

Technical Abstract:
We have shown previously that water soluble complexes from cinnamon enhance insulin function in vitro. Since insulin affects glucose and lipid metabolism, the objective of this study was to determine if cinnamon improves blood glucose, triglycerides, total cholesterol, high-density lipoprotein cholesterol (HDL) and low-density lipoprotein cholesterol (LDL) in people with type 2 diabetes mellitus (DM). Sixty people with type 2 DM, males and females, age 48 ± 6.5 years were divided into 6 groups. Groups 1, 2 and 3 consumed 1, 3 or 6 g of cinnamon/day respectively and groups 4, 5 and 6 were given placebo capsules corresponding to the number of capsules consumed for the three levels of cinnamon. The cinnamon was consumed for 40 days followed by a 20 day washout period. All three levels of cinnamon reduced the mean fasting serum glucose, triglycerides, LDL and total cholesterol levels with no changes in the placebo groups. Decreases in serum glucose ranged from 18 to 29%; triglycerides, 23 to 30%, and total cholesterol 12 to 26 % after 40 days of consuming cinnamon. Changes in HDL cholesterol were inconsistent. These results demonstrate that intake of 1, 3 or 6 grams of cinnamon per day reduces serum glucose, triglycerides, LDL and total cholesterol in people with type 2 DM. These data strongly suggest that the inclusion of cinnamon to the diet of people with type 2 DM will reduce risk factors associated with diabetes and cardiovascular diseases.